Rice research team's study keeps CO2-to-fuel devices running 50 times longer

new findings

Ahmad Elgazzar, Haotian Wang and Shaoyun Hao were members of a Rice University team that recently published findings on how acid bubbling can improve CO2 reduction systems. Photo courtesy Rice.

In a new study published in the journal Science, a team of Rice University researchers shared findings on how acid bubbles can improve the stability of electrochemical devices that convert carbon dioxide into useful fuels and chemicals.

The team led by Rice associate professor Hoatian Wang addressed an issue in the performance and stability of CO2 reduction systems. The gas flow channels in the systems often clog due to salt buildup, reducing efficiency and causing the devices to fail prematurely after about 80 hours of operation.

“Salt precipitation blocks CO2 transport and floods the gas diffusion electrode, which leads to performance failure,” Wang said in a news release. “This typically happens within a few hundred hours, which is far from commercial viability.”

By using an acid-humidified CO2 technique, the team was able to extend the operational life of a CO2 reduction system more than 50-fold, demonstrating more than 4,500 hours of stable operation in a scaled-up reactor.

The Rice team made a simple swap with a significant impact. Instead of using water to humidify the CO2 gas input into the reactor, the team bubbled the gas through an acid solution such as hydrochloric, formic or acetic acid. This process made more soluble salt formations that did not crystallize or block the channels.

The process has major implications for an emerging green technology known as electrochemical CO2 reduction, or CO2RR, that transforms climate-warming CO2 into products like carbon monoxide, ethylene, or alcohols. The products can be further refined into fuels or feedstocks.

“Using the traditional method of water-humidified CO2 could lead to salt formation in the cathode gas flow channels,” Shaoyun Hao, postdoctoral research associate in chemical and biomolecular engineering at Rice and co-first author, explained in the news release. “We hypothesized — and confirmed — that acid vapor could dissolve the salt and convert the low solubility KHCO3 into salt with higher solubility, thus shifting the solubility balance just enough to avoid clogging without affecting catalyst performance.”

The Rice team believes the work can lead to more scalable CO2 electrolyzers, which is vital if the technology is to be deployed at industrial scales as part of carbon capture and utilization strategies. Since the approach itself is relatively simple, it could lead to a more cost-effective and efficient solution. It also worked well with multiple catalyst types, including zinc oxide, copper oxide and bismuth oxide, which are allo used to target different CO2RR products.

“Our method addresses a long-standing obstacle with a low-cost, easily implementable solution,” Ahmad Elgazzar, co-first author and graduate student in chemical and biomolecular engineering at Rice, added in the release. “It’s a step toward making carbon utilization technologies more commercially viable and more sustainable.”

A team led by Wang and in collaboration with researchers from the University of Houston also shared findings on salt precipitation buildup and CO2RR in a recent edition of the journal Nature Energy. Read more here.

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Houston researchers develop strong biomaterial that could replace plastic

plastic problem

Collaborators from two Houston universities are leading the way in engineering a biomaterial into a scalable, multifunctional material that could potentially replace plastic.

The research was led by Muhammad Maksud Rahman, an assistant professor of mechanical and aerospace engineering at the University of Houston and an adjunct assistant professor of materials science and nanoengineering at Rice University. The team shared its findings in a study in the journal Nature Communications earlier this month. M.A.S.R. Saadi, a doctoral student in material science and nanoengineering at Rice, served as the first author.

The study introduced a biosynthesis technique that aligns bacterial cellulose fibers in real-time, which resulted in robust biopolymer sheets with “exceptional mechanical properties,” according to the researchers.

Biomaterials typically have weaker mechanical properties than their synthetic counterparts. However, the team was able to develop sheets of material with similar strengths to some metals and glasses. And still, the material was foldable and fully biodegradable.

To achieve this, the team developed a rotational bioreactor and utilized fluid motion to guide the bacteria fibers into a consistent alignment, rather than allowing them to align randomly, as they would in nature.

The process also allowed the team to easily integrate nanoscale additives—like graphene, carbon nanotubes and boron nitride—making the sheets stronger and improving the thermal properties.

“This dynamic biosynthesis approach enables the creation of stronger materials with greater functionality,” Saadi said in a release. “The method allows for the easy integration of various nanoscale additives directly into the bacterial cellulose, making it possible to customize material properties for specific applications.”

Ultimately, the scientists at UH and Rice hope this discovery could be used for the “next disposable water bottle,” which would be made by biodegradable biopolymers in bacterial cellulose, an abundant resource on Earth.

Additionally, the team sees applications for the materials in the packaging, breathable textiles, electronics, food and energy sectors.

“We envision these strong, multifunctional and eco-friendly bacterial cellulose sheets becoming ubiquitous, replacing plastics in various industries and helping mitigate environmental damage,” Rahman said the release.

America's only rare earth producer announces $500M agreement with Apple

Digging In

MP Materials, which runs the only American rare earths mine, announced a new $500 million agreement with tech giant Apple on Tuesday to produce more of the powerful magnets used in iPhones as well as other high-tech products like electric vehicles.

This news comes on the heels of last week’s announcement that the U.S. Defense Department agreed to invest $400 million in shares of the Las Vegas-based company. That will make the government the largest shareholder in MP Materials and help increase magnet production.

Despite their name, the 17 rare earth elements aren’t actually rare, but it’s hard to find them in a high enough concentration to make a mine worth the investment.

They are important ingredients in everything from smartphones and submarines to EVs and fighter jets, and it's those military applications that have made rare earths a key concern in ongoing U.S. trade talks. That's because China dominates the market and imposed new limits on exports after President Donald Trump announced his widespread tariffs. When shipments dried up, the two sides sat down in London.

The agreement with Apple will allow MP Materials to further expand its new factory in Texas to use recycled materials to produce the magnets that make iPhones vibrate. The company expects to start producing magnets for GM's electric vehicles later this year and this agreement will let it start producing magnets for Apple in 2027.

The Apple agreement represents a sliver of the company's pledge to invest $500 billion domestically during the Trump administration. And although the deal will provide a significant boost for MP Materials, the agreement with the Defense Department may be even more meaningful.

Neha Mukherjee, a rare earths analyst with Benchmark Mineral Intelligence, said in a research note that the Pentagon's 10-year promise to guarantee a minimum price for the key elements of neodymium and praseodymium will guarantee stable revenue for MP Minerals and protect it from potential price cuts by Chinese producers that are subsidized by their government.

“This is the kind of long-term commitment needed to reshape global rare earth supply chains," Mukherjee said.

Trump has made it a priority to try to reduce American reliance on China for rare earths. His administration is both helping MP Materials and trying to encourage the development of new mines that would take years to come to fruition. China has agreed to issue some permits for rare earth exports but not for military uses, and much uncertainty remains about their supply. The fear is that the trade war between the world’s two biggest economies could lead to a critical shortage of rare earth elements that could disrupt production of a variety of products. MP Materials can't satisfy all of the U.S. demand from its Mountain Pass mine in California’s Mojave Desert.

The deals by MP Materials come as Beijing and Washington have agreed to walk back on their non-tariff measures: China is to grant export permits for rare earth magnets to the U.S., and the U.S. is easing export controls on chip design software and jet engines. The truce is intended to ease tensions and prevent any catastrophic fall-off in bilateral relations, but is unlikely to address fundamental differences as both governments take steps to reduce dependency on each other.

Houston energy tech platform Molecule closes series B funding

energy software

Houston-based energy trading risk management (ETRM) software company Molecule has completed a successful series B round for an undisclosed amount, according to a July 16 release from the company.

The raise was led by Sundance Growth, a California-based software growth equity firm.

Sameer Soleja, founder and CEO of Molecule, said in the release that the funding will allow the company to "double down on product innovation, grow our team, and reach even more markets."

Molecule closed a $12 million Series A round in 2021, led by Houston-based Mercury Fund, and has since seen significant growth. The company, which was founded in 2012, has expanded its customer base across the U.S., U.K., Europe, Canada and South America, according to the release.

Additionally, it has launched two new modules of its software platform. Its Hive module, which debuted in 2022, enables clients to manage their energy portfolio and renewable credits together in one scalable platform. It also introduced Elektra, an add-on for the power market to its platform, which allows for complex power market trading.

"Four years ago, we committed to becoming the leading platform for energy trading," Soleja said in the release. "Today, our customers are managing complex power and renewable portfolios across multiple jurisdictions, all within Molecule.”

Molecule is also known for its data-as-a-lake platform, Bigbang, which enables energy ETRM and commodities trading and risk management (CTRM) customers to automatically import trade data from Molecule and then merge it with various sources to conduct queries and analysis.

“Molecule is doing something very few companies in energy tech have done: combining mission-critical depth with cloud-native, scalable technology,” Christian Stewart, Sundance Growth managing director, added in the statement. “Sameer and his team have built a platform that’s not only powerful, but user-friendly—a rare combination in enterprise software. We’re thrilled to partner with Molecule as they continue to grow and transform the energy trading and risk management market.”

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